Equity - Changes in Number of Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Common Class A
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	650,000
Ending balance (in shares)	654,000
Common Class B
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	377,000
Ending balance (in shares)	377,000
Common Stock | Common Class A
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	650,065	513,399
Issue of shares for employee stock purchase plan (in shares)	668	0
Ending balance (in shares)	653,749	514,940
Common Stock | Common Class A | Restricted Stock Units (RSUs)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares upon vesting of restricted stock units (in shares)	3,011	1,377
Common Stock | Common Class A | Options
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares on exercises of stock options (in shares)	5	164
Common Stock | Common Class B
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	377,428	521,543
Issue of shares for employee stock purchase plan (in shares)	0	0
Ending balance (in shares)	377,428	521,543
Common Stock | Common Class B | Restricted Stock Units (RSUs)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares upon vesting of restricted stock units (in shares)	0	0
Common Stock | Common Class B | Options
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares on exercises of stock options (in shares)	0	0